text: /*-
   * Copyright (c) 2010 The FreeBSD Foundation
   * All rights reserved.
   *
   * This software was developed by Shteryana Sotirova Shopova under
   * sponsorship from the FreeBSD Foundation.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * $FreeBSD$
   */
  #include <sys/queue.h>
  #include <sys/types.h>
  
  #include <errno.h>
  #include <stdarg.h>
  #include <stdlib.h>
  #include <stdio.h>
  #include <stdint.h>
  #include <string.h>
  #include <syslog.h>
  
  #include "asn1.h"
  #include "snmp.h"
  #include "snmpmod.h"
  
  #include "vacm_tree.h"
  #include "vacm_oid.h"
  
  static struct lmodule *vacm_module;
  /* For the registration. */
  static const struct asn_oid oid_vacm = OIDX_snmpVacmMIB;
  
  static uint reg_vacm;
  
  static int32_t vacm_lock;
  
  /*
   * Internal datastructures and forward declarations.
   */
  static void		vacm_append_userindex(struct asn_oid *,
      uint, const struct vacm_user *);
  static int		vacm_user_index_decode(const struct asn_oid *,
      uint, int32_t *, char *);
  static struct vacm_user *vacm_get_user(const struct asn_oid *,
      uint);
  static struct vacm_user *vacm_get_next_user(const struct asn_oid *,
      uint);
  static void		vacm_append_access_rule_index(struct asn_oid *,
      uint, const struct vacm_access *);
  static int		vacm_access_rule_index_decode(const struct asn_oid *,
      uint, char *, char *, int32_t *, int32_t *);
  static struct vacm_access *	vacm_get_access_rule(const struct asn_oid *,
      uint);
  static struct vacm_access *	vacm_get_next_access_rule(const struct asn_oid *,
      uint);
  static int		vacm_view_index_decode(const struct asn_oid *, uint,
      char *, struct asn_oid *);
  static void		vacm_append_viewindex(struct asn_oid *, uint,
      const struct vacm_view *);
  static struct vacm_view	*vacm_get_view(const struct asn_oid *, uint);
  static struct vacm_view	*vacm_get_next_view(const struct asn_oid *, uint);
  static struct vacm_view *vacm_get_view_by_name(u_char *, u_int);
  static struct vacm_context	*vacm_get_context(const struct asn_oid *, uint);
  static struct vacm_context	*vacm_get_next_context(const struct asn_oid *,
      uint);
  static void			vacm_append_ctxindex(struct asn_oid *, uint,
      const struct vacm_context *);
  
  int
  op_vacm_context(struct snmp_context *ctx __unused, struct snmp_value *val,
      uint32_t sub, uint32_t iidx __unused, enum snmp_op op)
  {
  	char cname[SNMP_ADM_STR32_SIZ];
  	size_t cnamelen;
  	struct vacm_context *vacm_ctx;
  
  	if (val->var.subs[sub - 1] != LEAF_vacmContextName)
  		abort();
  
  	switch (op) {
  	case SNMP_OP_GET:
  		if ((vacm_ctx = vacm_get_context(&val->var, sub)) == NULL)
  			return (SNMP_ERR_NOSUCHNAME);
  		break;
  
  	case SNMP_OP_GETNEXT:
  		if ((vacm_ctx = vacm_get_next_context(&val->var, sub)) == NULL)
  			return (SNMP_ERR_NOSUCHNAME);
  		vacm_append_ctxindex(&val->var, sub, vacm_ctx);
  		break;
  
  	case SNMP_OP_SET:
  		if ((vacm_ctx = vacm_get_context(&val->var, sub)) != NULL)
  			return (SNMP_ERR_WRONG_VALUE);
  		if (community != COMM_INITIALIZE)
  			return (SNMP_ERR_NOT_WRITEABLE);
  		if (val->var.subs[sub] >= SNMP_ADM_STR32_SIZ)
  			return (SNMP_ERR_WRONG_VALUE);
  		if (index_decode(&val->var, sub, iidx, &cname, &cnamelen))
  			return (SNMP_ERR_GENERR);
  		cname[cnamelen] = '\0';
  		if ((vacm_ctx = vacm_add_context(cname, reg_vacm)) == NULL)
  			return (SNMP_ERR_GENERR);
  		return (SNMP_ERR_NOERROR);
  
  	case SNMP_OP_COMMIT:
  		/* FALLTHROUGH*/
  	case SNMP_OP_ROLLBACK:
  		return (SNMP_ERR_NOERROR);
  	default:
  		abort();
  	}
  
  	return (string_get(val, vacm_ctx->ctxname, -1));
  }
  
  int
  op_vacm_security_to_group(struct snmp_context *ctx, struct snmp_value *val,
      uint32_t sub, uint32_t iidx __unused, enum snmp_op op)
  {
  	int32_t smodel;
  	char uname[SNMP_ADM_STR32_SIZ];
  	struct vacm_user *user;
  
  	switch (op) {
  	case SNMP_OP_GET:
  		if ((user = vacm_get_user(&val->var, sub)) == NULL)
  			return (SNMP_ERR_NOSUCHNAME);
  		break;
  
  	case SNMP_OP_GETNEXT:
  		if ((user = vacm_get_next_user(&val->var, sub)) == NULL)
  			return (SNMP_ERR_NOSUCHNAME);
  		vacm_append_userindex(&val->var, sub, user);
  		break;
  
  	case SNMP_OP_SET:
  		if ((user = vacm_get_user(&val->var, sub)) == NULL &&
  		    val->var.subs[sub - 1] != LEAF_vacmSecurityToGroupStatus)
  			return (SNMP_ERR_NOSUCHNAME);
  
  		if (user != NULL) {
  			if (community != COMM_INITIALIZE &&
  			    user->type == StorageType_readOnly)
  				return (SNMP_ERR_NOT_WRITEABLE);
  			if (user->status == RowStatus_active &&
  			    val->v.integer != RowStatus_destroy)
  				return (SNMP_ERR_INCONS_VALUE);
  		}
  
  		switch (val->var.subs[sub - 1]) {
  		case LEAF_vacmGroupName:
  			ctx->scratch->ptr1 = user->group->groupname;
  			ctx->scratch->int1 = strlen(user->group->groupname);
  			return (vacm_user_set_group(user,
  			    val->v.octetstring.octets,val->v.octetstring.len));
  
  		case LEAF_vacmSecurityToGroupStorageType:
  			return (SNMP_ERR_INCONS_VALUE);
  
  		case LEAF_vacmSecurityToGroupStatus:
  			if (user == NULL) {
  				if (val->v.integer != RowStatus_createAndGo ||
  				    vacm_user_index_decode(&val->var, sub,
  				    &smodel, uname) < 0)
  					return (SNMP_ERR_INCONS_VALUE);
  				user = vacm_new_user(smodel, uname);
  				if (user == NULL)
  					return (SNMP_ERR_GENERR);
  				user->status = RowStatus_destroy;
  				if (community != COMM_INITIALIZE)
  					user->type = StorageType_volatile;
  				else
  					user->type = StorageType_readOnly;
  			} else if (val->v.integer != RowStatus_active &&
  			    val->v.integer != RowStatus_destroy)
  				return (SNMP_ERR_INCONS_VALUE);
  			ctx->scratch->int1 = user->status;
  			user->status = val->v.integer;
  			break;
  		}
  		return (SNMP_ERR_NOERROR);
  
  	case SNMP_OP_COMMIT:
  		if (val->var.subs[sub - 1] != LEAF_vacmSecurityToGroupStatus)
  			return (SNMP_ERR_NOERROR);
  		if ((user = vacm_get_user(&val->var, sub)) == NULL)
  			return (SNMP_ERR_GENERR);
  		switch (val->v.integer) {
  		case  RowStatus_destroy:
  			return (vacm_delete_user(user));
  
  		case RowStatus_createAndGo:
  			user->status = RowStatus_active;
  			break;
  
  		default:
  			break;
  		}
  		return (SNMP_ERR_NOERROR);
  
  	case SNMP_OP_ROLLBACK:
  		if ((user = vacm_get_user(&val->var, sub)) == NULL)
  			return (SNMP_ERR_GENERR);
  		switch (val->var.subs[sub - 1]) {
  		case LEAF_vacmGroupName:
  			return (vacm_user_set_group(user, ctx->scratch->ptr1,
  			    ctx->scratch->int1));
  
  		case LEAF_vacmSecurityToGroupStatus:
  			if (ctx->scratch->int1 == RowStatus_destroy)
  				return (vacm_delete_user(user));
  			user->status = ctx->scratch->int1;
  			break;
  
  		default:
  			break;
  		}
  		return (SNMP_ERR_NOERROR);
  
  	default:
  		abort();
  	}
  
  	switch (val->var.subs[sub - 1]) {
  	case LEAF_vacmGroupName:
  		return (string_get(val, user->group->groupname, -1));
  	case LEAF_vacmSecurityToGroupStorageType:
  		val->v.integer = user->type;
  		break;
  	case LEAF_vacmSecurityToGroupStatus:
  		val->v.integer = user->status;
  		break;
  	default:
  		abort();
  	}
  
  	return (SNMP_ERR_NOERROR);
  }
  
  int
  op_vacm_access(struct snmp_context *ctx, struct snmp_value *val, uint32_t sub,
      uint32_t iidx __unused, enum snmp_op op)
  {
  	int32_t smodel, slevel;
  	char gname[SNMP_ADM_STR32_SIZ], cprefix[SNMP_ADM_STR32_SIZ];
  	struct vacm_access *acl;
  
  	switch (op) {
  	case SNMP_OP_GET:
  		if ((acl = vacm_get_access_rule(&val->var, sub)) == NULL)
  			return (SNMP_ERR_NOSUCHNAME);
  		break;
  
  	case SNMP_OP_GETNEXT:
  		if ((acl = vacm_get_next_access_rule(&val->var, sub)) == NULL)
  			return (SNMP_ERR_NOSUCHNAME);
  		vacm_append_access_rule_index(&val->var, sub, acl);
  		break;
  
  	case SNMP_OP_SET:
  		if ((acl = vacm_get_access_rule(&val->var, sub)) == NULL &&
  		    val->var.subs[sub - 1] != LEAF_vacmAccessStatus)
  				return (SNMP_ERR_NOSUCHNAME);
  		if (acl != NULL && community != COMM_INITIALIZE &&
  		    acl->type == StorageType_readOnly)
  			return (SNMP_ERR_NOT_WRITEABLE);
  
  		switch (val->var.subs[sub - 1]) {
  		case LEAF_vacmAccessContextMatch:
  			ctx->scratch->int1 = acl->ctx_match;
  			if (val->v.integer == vacmAccessContextMatch_exact)
  				acl->ctx_match = 1;
  			else if (val->v.integer == vacmAccessContextMatch_prefix)
  				acl->ctx_match = 0;
  			else
  				return (SNMP_ERR_WRONG_VALUE);
  			break;
  
  		case LEAF_vacmAccessReadViewName:
  			ctx->scratch->ptr1 = acl->read_view;
  			acl->read_view = vacm_get_view_by_name(val->v.octetstring.octets, val->v.octetstring.len);
  			if (acl->read_view == NULL) {
  				acl->read_view = ctx->scratch->ptr1;
  				return (SNMP_ERR_INCONS_VALUE);
  			}
  			return (SNMP_ERR_NOERROR);
  
  		case LEAF_vacmAccessWriteViewName:
  			ctx->scratch->ptr1 = acl->write_view;
  			if ((acl->write_view =
  			    vacm_get_view_by_name(val->v.octetstring.octets,
  			    val->v.octetstring.len)) == NULL) {
  				acl->write_view = ctx->scratch->ptr1;
  				return (SNMP_ERR_INCONS_VALUE);
  			}
  			break;
  
  		case LEAF_vacmAccessNotifyViewName:
  			ctx->scratch->ptr1 = acl->notify_view;
  			if ((acl->notify_view =
  			    vacm_get_view_by_name(val->v.octetstring.octets,
  			    val->v.octetstring.len)) == NULL) {
  				acl->notify_view = ctx->scratch->ptr1;
  				return (SNMP_ERR_INCONS_VALUE);
  			}
  			break;
  
  		case LEAF_vacmAccessStorageType:
  			return (SNMP_ERR_INCONS_VALUE);
  
  		case LEAF_vacmAccessStatus:
  			if (acl == NULL) {
  				if (val->v.integer != RowStatus_createAndGo ||
  				    vacm_access_rule_index_decode(&val->var,
  				    sub, gname, cprefix, &smodel, &slevel) < 0)
  					return (SNMP_ERR_INCONS_VALUE);
  				if ((acl = vacm_new_access_rule(gname, cprefix,
  				    smodel, slevel)) == NULL)
  					return (SNMP_ERR_GENERR);
  				acl->status = RowStatus_destroy;
  				if (community != COMM_INITIALIZE)
  					acl->type = StorageType_volatile;
  				else
  					acl->type = StorageType_readOnly;
  			} else if (val->v.integer != RowStatus_active &&
  			    val->v.integer != RowStatus_destroy)
  				return (SNMP_ERR_INCONS_VALUE);
  			ctx->scratch->int1 = acl->status;
  			acl->status = val->v.integer;
  			break;
  		}
  		return (SNMP_ERR_NOERROR);
  
  	case SNMP_OP_COMMIT:
  		if (val->var.subs[sub - 1] != LEAF_vacmAccessStatus)
  			return (SNMP_ERR_NOERROR);
  		if ((acl = vacm_get_access_rule(&val->var, sub)) == NULL)
  			return (SNMP_ERR_GENERR);
  		if (val->v.integer == RowStatus_destroy)
  			return (vacm_delete_access_rule(acl));
  		else
  			acl->status = RowStatus_active;
  		return (SNMP_ERR_NOERROR);
  
  	case SNMP_OP_ROLLBACK:
  		if ((acl = vacm_get_access_rule(&val->var, sub)) == NULL)
  			return (SNMP_ERR_GENERR);
  		switch (val->var.subs[sub - 1]) {
  		case LEAF_vacmAccessContextMatch:
  			acl->ctx_match = ctx->scratch->int1;
  			break;
  		case LEAF_vacmAccessReadViewName:
  			acl->read_view = ctx->scratch->ptr1;
  			break;
  		case LEAF_vacmAccessWriteViewName:
  			acl->write_view = ctx->scratch->ptr1;
  			break;
  		case LEAF_vacmAccessNotifyViewName:
  			acl->notify_view = ctx->scratch->ptr1;
  			break;
  		case LEAF_vacmAccessStatus:
  			if (ctx->scratch->int1 == RowStatus_destroy)
  				return (vacm_delete_access_rule(acl));
  		default:
  			break;
  		}
  		return (SNMP_ERR_NOERROR);
  
  	default:
  		abort();
  	}
  
  	switch (val->var.subs[sub - 1]) {
  	case LEAF_vacmAccessContextMatch:
  		return (string_get(val, acl->ctx_prefix, -1));
  	case LEAF_vacmAccessReadViewName:
  		if (acl->read_view != NULL)
  			return (string_get(val, acl->read_view->viewname, -1));
  		else
  			return (string_get(val, NULL, 0));
  	case LEAF_vacmAccessWriteViewName:
  		if (acl->write_view != NULL)
  			return (string_get(val, acl->write_view->viewname, -1));
  		else
  			return (string_get(val, NULL, 0));
  	case LEAF_vacmAccessNotifyViewName:
  		if (acl->notify_view != NULL)
  			return (string_get(val, acl->notify_view->viewname, -1));
  		else
  			return (string_get(val, NULL, 0));
  	case LEAF_vacmAccessStorageType:
  		val->v.integer = acl->type;
  		break;
  	case LEAF_vacmAccessStatus:
  		val->v.integer = acl->status;
  		break;
  	default:
  		abort();
  	}
  
  	return (SNMP_ERR_NOERROR);
  }
  
  int
  op_vacm_view_lock(struct snmp_context *ctx __unused, struct snmp_value *val,
      uint32_t sub, uint32_t iidx __unused, enum snmp_op op)
  {
  	if (val->var.subs[sub - 1] != LEAF_vacmViewSpinLock)
  		return (SNMP_ERR_NOSUCHNAME);
  
  	switch (op) {
  	case SNMP_OP_GET:
  		if (++vacm_lock == INT32_MAX)
  			vacm_lock = 0;
  		val->v.integer = vacm_lock;
  		break;
  
  	case SNMP_OP_GETNEXT:
  		abort();
  
  	case SNMP_OP_SET:
  		if (val->v.integer != vacm_lock)
  			return (SNMP_ERR_INCONS_VALUE);
  		break;
  
  	case SNMP_OP_ROLLBACK:
  		/* FALLTHROUGH */
  	case SNMP_OP_COMMIT:
  		break;
  	}
  
  	return (SNMP_ERR_NOERROR);
  }
  
  int
  op_vacm_view(struct snmp_context *ctx, struct snmp_value *val, uint32_t sub,
      uint32_t iidx __unused, enum snmp_op op)
  {
  	char vname[SNMP_ADM_STR32_SIZ];
  	struct asn_oid oid;
  	struct vacm_view *view;
  
  	switch (op) {
  	case SNMP_OP_GET:
  		if ((view = vacm_get_view(&val->var, sub)) == NULL)
  			return (SNMP_ERR_NOSUCHNAME);
  		break;
  
  	case SNMP_OP_GETNEXT:
  		if ((view = vacm_get_next_view(&val->var, sub)) == NULL)
  			return (SNMP_ERR_NOSUCHNAME);
  		vacm_append_viewindex(&val->var, sub, view);
  		break;
  
  	case SNMP_OP_SET:
  		if ((view = vacm_get_view(&val->var, sub)) == NULL &&
  		    val->var.subs[sub - 1] != LEAF_vacmViewTreeFamilyStatus)
  				return (SNMP_ERR_NOSUCHNAME);
  
  		if (view != NULL) {
  			if (community != COMM_INITIALIZE &&
  			    view->type == StorageType_readOnly)
  				return (SNMP_ERR_NOT_WRITEABLE);
  			if (view->status == RowStatus_active &&
  			    val->v.integer != RowStatus_destroy)
  				return (SNMP_ERR_INCONS_VALUE);
  		}
  
  		switch (val->var.subs[sub - 1]) {
  		case LEAF_vacmViewTreeFamilyMask:
  			if (val->v.octetstring.len > sizeof(view->mask))
  			ctx->scratch->ptr1 = malloc(sizeof(view->mask));
  			if (ctx->scratch->ptr1 == NULL)
  				return (SNMP_ERR_GENERR);
  			memset(ctx->scratch->ptr1, 0, sizeof(view->mask));
  			memcpy(ctx->scratch->ptr1, view->mask,
  			    sizeof(view->mask));
  			memset(view->mask, 0, sizeof(view->mask));
  			memcpy(view->mask, val->v.octetstring.octets,
  			    val->v.octetstring.len);
  			break;
  
  		case LEAF_vacmViewTreeFamilyType:
  			ctx->scratch->int1 = view->exclude;
  			if (val->v.integer == vacmViewTreeFamilyType_included)
  				view->exclude = 0;
  			else if (val->v.integer == vacmViewTreeFamilyType_excluded)
  				view->exclude = 1;
  			else
  				return (SNMP_ERR_WRONG_VALUE);
  			break;
  
  		case LEAF_vacmViewTreeFamilyStorageType:
  			return (SNMP_ERR_INCONS_VALUE);
  
  		case LEAF_vacmViewTreeFamilyStatus:
  			if (view == NULL) {
  				if (val->v.integer != RowStatus_createAndGo ||
  				    vacm_view_index_decode(&val->var, sub, vname,
  				    &oid) < 0)
  					return (SNMP_ERR_INCONS_VALUE);
  				if ((view = vacm_new_view(vname, &oid)) == NULL)
  					return (SNMP_ERR_GENERR);
  				view->status = RowStatus_destroy;
  				if (community != COMM_INITIALIZE)
  					view->type = StorageType_volatile;
  				else
  					view->type = StorageType_readOnly;
  			} else if (val->v.integer != RowStatus_active &&
  			    val->v.integer != RowStatus_destroy)
  				return (SNMP_ERR_INCONS_VALUE);
  			ctx->scratch->int1 = view->status;
  			view->status = val->v.integer;
  			break;
  		}
  		return (SNMP_ERR_NOERROR);
  
  	case SNMP_OP_COMMIT:
  		switch (val->var.subs[sub - 1]) {
  		case LEAF_vacmViewTreeFamilyMask:
  			free(ctx->scratch->ptr1);
  			break;
  		case LEAF_vacmViewTreeFamilyStatus:
  			if ((view = vacm_get_view(&val->var, sub)) == NULL)
  				return (SNMP_ERR_GENERR);
  			switch (val->v.integer) {
  			case  RowStatus_destroy:
  				return (vacm_delete_view(view));
  
  			case RowStatus_createAndGo:
  				view->status = RowStatus_active;
  				break;
  
  			default:
  				/* NOTREACHED*/
  				return (SNMP_ERR_GENERR);
  			}
  		default:
  			break;
  		}
  		return (SNMP_ERR_NOERROR);
  
  	case SNMP_OP_ROLLBACK:
  		if ((view = vacm_get_view(&val->var, sub)) == NULL)
  			return (SNMP_ERR_GENERR);
  		switch (val->var.subs[sub - 1]) {
  		case LEAF_vacmViewTreeFamilyMask:
  			memcpy(view->mask, ctx->scratch->ptr1,
  			    sizeof(view->mask));
  			free(ctx->scratch->ptr1);
  			break;
  		case LEAF_vacmViewTreeFamilyType:
  			view->exclude = ctx->scratch->int1;
  			break;
  		case LEAF_vacmViewTreeFamilyStatus:
  			if (ctx->scratch->int1 == RowStatus_destroy)
  				return (vacm_delete_view(view));
  			break;
  		default:
  			break;	
  		}
  		return (SNMP_ERR_NOERROR);
  
  	default:
  		abort();
  	}
  
  	switch (val->var.subs[sub - 1]) {
  	case LEAF_vacmViewTreeFamilyMask:
  		return (string_get(val, view->mask, sizeof(view->mask)));
  	case LEAF_vacmViewTreeFamilyType:
  		if (view->exclude)
  			val->v.integer = vacmViewTreeFamilyType_excluded;
  		else
  			val->v.integer = vacmViewTreeFamilyType_included;
  		break;
  	case LEAF_vacmViewTreeFamilyStorageType:
  		val->v.integer = view->type;
  		break;
  	case LEAF_vacmViewTreeFamilyStatus:
  		val->v.integer = view->status;
  		break;
  	default:
  		abort();
  	}
  
  	return (SNMP_ERR_NOERROR);
  }
  
  static void
  vacm_append_userindex(struct asn_oid *oid, uint sub,
      const struct vacm_user *user)
  {
  	uint32_t i;
  
  	oid->len = sub + strlen(user->secname) + 2;
  	oid->subs[sub++] = user->sec_model;
  	oid->subs[sub] = strlen(user->secname);
  	for (i = 1; i <= strlen(user->secname); i++)
  		oid->subs[sub + i] = user->secname[i - 1];
  }
  
  static int
  vacm_user_index_decode(const struct asn_oid *oid, uint sub,
      int32_t *smodel, char *uname)
  {
  	uint32_t i;
  
  	*smodel = oid->subs[sub++];
  
  	if (oid->subs[sub] >= SNMP_ADM_STR32_SIZ)
  		return (-1);
  
  	for (i = 0; i < oid->subs[sub]; i++)
  		uname[i] = oid->subs[sub + i + 1];
  	uname[i] = '\0';
  
  	return (0);
  }
  
  static struct vacm_user *
  vacm_get_user(const struct asn_oid *oid, uint sub)
  {
  	int32_t smodel;
  	char uname[SNMP_ADM_STR32_SIZ];
  	struct vacm_user *user;
  
  	if (vacm_user_index_decode(oid, sub, &smodel, uname) < 0)
  		return (NULL);
  
  	for (user = vacm_first_user(); user != NULL; user = vacm_next_user(user))
  		if (strcmp(uname, user->secname) == 0 &&
  		    user->sec_model == smodel)
  			return (user);
  
  	return (NULL);
  }
  
  static struct vacm_user *
  vacm_get_next_user(const struct asn_oid *oid, uint sub)
  {
  	int32_t smodel;
  	char uname[SNMP_ADM_STR32_SIZ];
  	struct vacm_user *user;
  
  	if (oid->len - sub == 0)
  		return (vacm_first_user());
  
  	if (vacm_user_index_decode(oid, sub, &smodel, uname) < 0)
  		return (NULL);
  
  	for (user = vacm_first_user(); user != NULL; user = vacm_next_user(user))
  		if (strcmp(uname, user->secname) == 0 &&
  		    user->sec_model == smodel)
  			return (vacm_next_user(user));
  
  	return (NULL);
  }
  
  static void
  vacm_append_access_rule_index(struct asn_oid *oid, uint sub,
      const struct vacm_access *acl)
  {
  	uint32_t i;
    
  	oid->len = sub + strlen(acl->group->groupname) +
  	    strlen(acl->ctx_prefix) + 4;
  
  	oid->subs[sub] = strlen(acl->group->groupname);
  	for (i = 1; i <= strlen(acl->group->groupname); i++)
  		oid->subs[sub + i] = acl->group->groupname[i - 1];
  	sub += strlen(acl->group->groupname) + 1;
  
  	oid->subs[sub] = strlen(acl->ctx_prefix);
  	for (i = 1; i <= strlen(acl->ctx_prefix); i++)
  		oid->subs[sub + i] = acl->ctx_prefix[i - 1];
  	sub += strlen(acl->ctx_prefix) + 1;
  	oid->subs[sub++] = acl->sec_model;
  	oid->subs[sub] = acl->sec_level;
  }
  
  static int
  vacm_access_rule_index_decode(const struct asn_oid *oid, uint sub, char *gname,
      char *cprefix, int32_t *smodel, int32_t *slevel)
  {
  	uint32_t i;
  
  	if (oid->subs[sub] >= SNMP_ADM_STR32_SIZ)
  		return (-1);
  
  	for (i = 0; i < oid->subs[sub]; i++)
  		gname[i] = oid->subs[sub + i + 1];
  	gname[i] = '\0';
  	sub += strlen(gname) + 1;
  
  	if (oid->subs[sub] >= SNMP_ADM_STR32_SIZ)
  		return (-1);
  
  	for (i = 0; i < oid->subs[sub]; i++)
  		cprefix[i] = oid->subs[sub + i + 1];
  	cprefix[i] = '\0';
  	sub += strlen(cprefix) + 1;
  
  	*smodel = oid->subs[sub++];
  	*slevel = oid->subs[sub];
  
  	return (0);
  }
  
  struct vacm_access *
  vacm_get_access_rule(const struct asn_oid *oid, uint sub)
  {
  	int32_t smodel, slevel;
  	char gname[SNMP_ADM_STR32_SIZ], prefix[SNMP_ADM_STR32_SIZ];
  	struct vacm_access *acl;
  
  	if (vacm_access_rule_index_decode(oid, sub, gname, prefix, &smodel,
  	    &slevel) < 0)
  		return (NULL);
  
  	for (acl = vacm_first_access_rule(); acl != NULL;
  	    acl = vacm_next_access_rule(acl))
  		if (strcmp(gname, acl->group->groupname) == 0 &&
  		    strcmp(prefix, acl->ctx_prefix) == 0 &&
  		    smodel == acl->sec_model && slevel == acl->sec_level)
  			return (acl);
  
  	return (NULL);
  }
  
  struct vacm_access *
  vacm_get_next_access_rule(const struct asn_oid *oid __unused, uint sub __unused)
  {
  	int32_t smodel, slevel;
  	char gname[SNMP_ADM_STR32_SIZ], prefix[SNMP_ADM_STR32_SIZ];
  	struct vacm_access *acl;
  
  	if (oid->len - sub == 0)
  		return (vacm_first_access_rule());
  
  	if (vacm_access_rule_index_decode(oid, sub, gname, prefix, &smodel,
  	    &slevel) < 0)
  		return (NULL);
  
  	for (acl = vacm_first_access_rule(); acl != NULL;
  	    acl = vacm_next_access_rule(acl))
  		if (strcmp(gname, acl->group->groupname) == 0 &&
  		    strcmp(prefix, acl->ctx_prefix) == 0 &&
  		    smodel == acl->sec_model && slevel == acl->sec_model)
  			return (vacm_next_access_rule(acl));
  
  	return (NULL);
  }
  
  static int
  vacm_view_index_decode(const struct asn_oid *oid, uint sub, char *vname,
     struct asn_oid *view_oid)
  {	
  	uint32_t i;
  	int viod_off;
  
  	if (oid->subs[sub] >= SNMP_ADM_STR32_SIZ)
  		return (-1);
  
  	for (i = 0; i < oid->subs[sub]; i++)
  		vname[i] = oid->subs[sub + i + 1];
  	vname[i] = '\0';
  
  	viod_off = sub + oid->subs[sub] + 1;
  	if ((view_oid->len = oid->subs[viod_off]) > ASN_MAXOIDLEN)
  		return (-1);
  
  	memcpy(&view_oid->subs[0], &oid->subs[viod_off + 1],
  	    view_oid->len * sizeof(view_oid->subs[0]));
  
  	return (0);
  }
  
  static void
  vacm_append_viewindex(struct asn_oid *oid, uint sub, const struct vacm_view *view)
  {
  	uint32_t i;
  
  	oid->len = sub + strlen(view->viewname) + 1;
  	oid->subs[sub] = strlen(view->viewname);
  	for (i = 1; i <= strlen(view->viewname); i++)
  		oid->subs[sub + i] = view->viewname[i - 1];
  
  	sub += strlen(view->viewname) + 1;
  	oid->subs[sub] = view->subtree.len;
  	oid->len++;
  	asn_append_oid(oid, &view->subtree);
  }
  
  struct vacm_view *
  vacm_get_view(const struct asn_oid *oid, uint sub)
  {
  	char vname[SNMP_ADM_STR32_SIZ];
  	struct asn_oid subtree;
  	struct vacm_view *view;
  
  	if (vacm_view_index_decode(oid, sub, vname, &subtree) < 0)
  		return (NULL);
  
  	for (view = vacm_first_view(); view != NULL; view = vacm_next_view(view))
  		if (strcmp(vname, view->viewname) == 0 &&
  		    asn_compare_oid(&subtree, &view->subtree)== 0)
  			return (view);
  
  	return (NULL);
  }
  
  struct vacm_view *
  vacm_get_next_view(const struct asn_oid *oid, uint sub)
  {
  	char vname[SNMP_ADM_STR32_SIZ];
  	struct asn_oid subtree;
  	struct vacm_view *view;
  
  	if (oid->len - sub == 0)
  		return (vacm_first_view());
  
  	if (vacm_view_index_decode(oid, sub, vname, &subtree) < 0)
  		return (NULL);
  
  	for (view = vacm_first_view(); view != NULL; view = vacm_next_view(view))
  		if (strcmp(vname, view->viewname) == 0 &&
  		    asn_compare_oid(&subtree, &view->subtree)== 0)
  			return (vacm_next_view(view));
  
  	return (NULL);
  }
  
  static struct vacm_view *
  vacm_get_view_by_name(u_char *octets, u_int len)
  {
  	struct vacm_view *view;
  
  	for (view = vacm_first_view(); view != NULL; view = vacm_next_view(view))
  		if (strlen(view->viewname) == len &&
  		    memcmp(octets, view->viewname, len) == 0)
  			return (view);
  
  	return (NULL);
  }
  
  static struct vacm_context *
  vacm_get_context(const struct asn_oid *oid, uint sub)
  {
  	char cname[SNMP_ADM_STR32_SIZ];
  	size_t cnamelen;
  	u_int index_count;
  	struct vacm_context *vacm_ctx;
  
  	if (oid->subs[sub] >= SNMP_ADM_STR32_SIZ)
  		return (NULL);
  
  	index_count = 0;
  	index_count = SNMP_INDEX(index_count, 1);
  	if (index_decode(oid, sub, index_count, &cname, &cnamelen))
  		return (NULL);
  
  	for (vacm_ctx = vacm_first_context(); vacm_ctx != NULL;
  	    vacm_ctx = vacm_next_context(vacm_ctx))
  		if (strcmp(cname, vacm_ctx->ctxname) == 0)
  			return (vacm_ctx);
  
  	return (NULL);
  }
  
  static struct vacm_context *
  vacm_get_next_context(const struct asn_oid *oid, uint sub)
  {
  	char cname[SNMP_ADM_STR32_SIZ];
  	size_t cnamelen;
  	u_int index_count;
  	struct vacm_context *vacm_ctx;
  
  	if (oid->len - sub == 0)
  		return (vacm_first_context());
  
  	if (oid->subs[sub] >= SNMP_ADM_STR32_SIZ)
  		return (NULL);
  
  	index_count = 0;
  	index_count = SNMP_INDEX(index_count, 1);
  	if (index_decode(oid, sub, index_count, &cname, &cnamelen))
  		return (NULL);
  
  	for (vacm_ctx = vacm_first_context(); vacm_ctx != NULL;
  	    vacm_ctx = vacm_next_context(vacm_ctx))
  		if (strcmp(cname, vacm_ctx->ctxname) == 0)
  			return (vacm_next_context(vacm_ctx));
  
  	return (NULL);
  }
  
  static void
  vacm_append_ctxindex(struct asn_oid *oid, uint sub,
      const struct vacm_context *ctx)
  {
  	uint32_t i;
  
  	oid->len = sub + strlen(ctx->ctxname) + 1;
  	oid->subs[sub] = strlen(ctx->ctxname);
  	for (i = 1; i <= strlen(ctx->ctxname); i++)
  		oid->subs[sub + i] = ctx->ctxname[i - 1];
  }
  
  /*
   * VACM snmp module initialization hook.
   * Returns 0 on success, < 0 on error.
   */
  static int
  vacm_init(struct lmodule *mod, int argc __unused, char *argv[] __unused)
  {
  	vacm_module = mod;
  	vacm_lock = random();
  	vacm_groups_init();
  
  	/* XXX: TODO - initialize structures */
  	return (0);
  }
  
  /*
   * VACM snmp module finalization hook.
   */
  static int
  vacm_fini(void)
  {
  	/* XXX: TODO - cleanup */
  	vacm_flush_contexts(reg_vacm);
  	or_unregister(reg_vacm);
  
  	return (0);
  }
  
  /*
   * VACM snmp module start operation.
   */
  static void
  vacm_start(void)
  {
  	static char dflt_ctx[] = "";
  
  	reg_vacm = or_register(&oid_vacm,
  	    "The MIB module for managing SNMP View-based Access Control Model.",
  	    vacm_module);
  
  	(void)vacm_add_context(dflt_ctx, reg_vacm);
  }
  
  static void
  vacm_dump(void)
  {
  	struct vacm_context *vacmctx;
  	struct vacm_user *vuser;
  	struct vacm_access *vacl;
  	struct vacm_view *view;
  	static char oidbuf[ASN_OIDSTRLEN];
  
  	syslog(LOG_ERR, "\n");
  	syslog(LOG_ERR, "Context list:");
  	for (vacmctx = vacm_first_context(); vacmctx != NULL;
  	    vacmctx = vacm_next_context(vacmctx))
  		syslog(LOG_ERR, "Context \"%s\", module id %d",
  		    vacmctx->ctxname, vacmctx->regid);
  
  	syslog(LOG_ERR, "VACM users:");
  	for (vuser = vacm_first_user(); vuser != NULL;
  	    vuser = vacm_next_user(vuser))
  		syslog(LOG_ERR, "Uname %s, Group %s, model %d", vuser->secname,
  		    vuser->group!= NULL?vuser->group->groupname:"Unknown",
  		    vuser->sec_model);
  
  	syslog(LOG_ERR, "VACM Access rules:");
  	for (vacl = vacm_first_access_rule(); vacl != NULL;
  	    vacl = vacm_next_access_rule(vacl))
  		syslog(LOG_ERR, "Group %s, CtxPrefix %s, Model %d, Level %d, "
  		    "RV %s, WR %s, NV %s", vacl->group!=NULL?
  		    vacl->group->groupname:"Unknown", vacl->ctx_prefix,
  		    vacl->sec_model, vacl->sec_level, vacl->read_view!=NULL?
  		    vacl->read_view->viewname:"None", vacl->write_view!=NULL?
  		    vacl->write_view->viewname:"None", vacl->notify_view!=NULL?
  		    vacl->notify_view->viewname:"None");
  
  	syslog(LOG_ERR, "VACM Views:");
  	for (view = vacm_first_view(); view != NULL; view = vacm_next_view(view))
  		syslog(LOG_ERR, "View %s, Tree %s - %s", view->viewname,
  		    asn_oid2str_r(&view->subtree, oidbuf), view->exclude?
  		    "excluded":"included");
  }
  
  const char vacm_comment[] = \
  "This module implements SNMP View-based Access Control Model defined in RFC 3415.";
  
  const struct snmp_module config = {
  	.comment =	vacm_comment,
  	.init =		vacm_init,
  	.fini =		vacm_fini,
  	.start =	vacm_start,
  	.tree =		vacm_ctree,
  	.dump =		vacm_dump,
  	.tree_size =	vacm_CTREE_SIZE,
  };
  